/*
给你一个数组 orders，表示客户在餐厅中完成的订单，确切地说， orders[i]=[customerNamei,tableNumberi,foodItemi] ，其中 customerNamei 是客户的姓名，tableNumberi 是客户所在餐桌的桌号，而 foodItemi 是客户点的餐品名称。

请你返回该餐厅的 点菜展示表 。在这张表中，表中第一行为标题，其第一列为餐桌桌号 “Table” ，后面每一列都是按字母顺序排列的餐品名称。接下来每一行中的项则表示每张餐桌订购的相应餐品数量，第一列应当填对应的桌号，后面依次填写下单的餐品数量。

注意：客户姓名不是点菜展示表的一部分。此外，表中的数据行应该按餐桌桌号升序排列。

 

示例 1：

输入：orders = [["David","3","Ceviche"],["Corina","10","Beef Burrito"],["David","3","Fried Chicken"],["Carla","5","Water"],["Carla","5","Ceviche"],["Rous","3","Ceviche"]]
输出：[["Table","Beef Burrito","Ceviche","Fried Chicken","Water"],["3","0","2","1","0"],["5","0","1","0","1"],["10","1","0","0","0"]] 
解释：
点菜展示表如下所示：
Table,Beef Burrito,Ceviche,Fried Chicken,Water
3    ,0           ,2      ,1            ,0
5    ,0           ,1      ,0            ,1
10   ,1           ,0      ,0            ,0
对于餐桌 3：David 点了 "Ceviche" 和 "Fried Chicken"，而 Rous 点了 "Ceviche"
而餐桌 5：Carla 点了 "Water" 和 "Ceviche"
餐桌 10：Corina 点了 "Beef Burrito" 
示例 2：

输入：orders = [["James","12","Fried Chicken"],["Ratesh","12","Fried Chicken"],["Amadeus","12","Fried Chicken"],["Adam","1","Canadian Waffles"],["Brianna","1","Canadian Waffles"]]
输出：[["Table","Canadian Waffles","Fried Chicken"],["1","2","0"],["12","0","3"]] 
解释：
对于餐桌 1：Adam 和 Brianna 都点了 "Canadian Waffles"
而餐桌 12：James, Ratesh 和 Amadeus 都点了 "Fried Chicken"
示例 3：

输入：orders = [["Laura","2","Bean Burrito"],["Jhon","2","Beef Burrito"],["Melissa","2","Soda"]]
输出：[["Table","Bean Burrito","Beef Burrito","Soda"],["2","1","1","1"]]
 

提示：

1 <= orders.length <= 5 * 10^4
orders[i].length == 3
1 <= customerNamei.length, foodItemi.length <= 20
customerNamei 和 foodItemi 由大小写英文字母及空格字符 ' ' 组成。
tableNumberi 是 1 到 500 范围内的整数。

来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/display-table-of-food-orders-in-a-restaurant
著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。
*/

#include "../stdc++.h"

class Solution {
public:
    vector<vector<string>> displayTable(vector<vector<string>>& orders) {
        unordered_set<string> foodNameSet{};
        unordered_map<int, unordered_map<string, int>> foodCounts{};
        for (auto& order : orders) {
            foodNameSet.insert(order[2]);
            int id = stoi(order[1]);
            ++foodCounts[id][order[2]];
        }

        // 提取餐品名称，并按字母顺序排列
        int n = foodNameSet.size();
        vector<string> foodNames(foodNameSet.begin(), foodNameSet.end());
        sort(foodNames.begin(), foodNames.end());

        // 提取桌号，并按餐桌桌号升序排列
        int m = foodCounts.size();
        vector<int> tableIds{};
        for (auto& p : foodCounts) {
            tableIds.emplace_back(p.first);
        }
        sort(tableIds.begin(), tableIds.end());

        vector<vector<string>> res(m + 1, vector<string>(n + 1));
        res[0][0] = "Table";
        copy(foodNames.begin(), foodNames.end(), res[0].begin() + 1); // OutputIt copy( InputIt first, InputIt last, OutputIt d_first );
        for (int i{0}; i < m; ++i) {
            int tableId = tableIds[i];
            auto& foodCount = foodCounts[tableId];
            res[i + 1][0] = to_string(tableId);
            for (int j{0}; j < n; ++j) {
                res[i + 1][j + 1] = to_string(foodCount[foodNames[j]]);
            }
        }
        return res;
    }
};